Decorative oil lamp



FIG. 1 is a front elevation of my design for a decorative oil lamp.

FIG. 2 is a rear elevation thereof.

FIG. 3 is a side elevation thereof.

FIG. 4 is a side elevation thereof opposite that of FIG. 3.

FIG. 5 is a top plan view thereof.

FIG. 6 is a bottom plan view thereof. 

The ornamental design for a decorative oil lamp, as shown. 